The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 16, 2022
Filed:
Mar. 27, 2020
United Microelectronics Corp., Hsinchu, TW;
Zhuona Ma, Singapore, SG;
Mengkai Zhu, Singapore, SG;
Runshun Wang, Singapore, SG;
Hua-Kuo Lee, Singapore, SG;
UNITED MICROELECTRONICS CORP., Hsinchu, TW;
Abstract
A method for fabricating a semiconductor device is provided. The method includes providing a substrate, having a cell region and a logic region and including a first conductive layer as a top layer, wherein shallow trench isolation (STI) structures are disposed in the substrate at cell region and the logic region. A first dry etching process is performed to preliminarily etch the first conductive layer and the STI structures at the cell region. A wet etching process is performed over the substrate to etch the STI structures down to a preserved height. A control gate stack is formed on the first conductive layer at the cell region. A second dry etching process is performed on a portion of the first conductive layer to form a floating gate under the control gate stack at the cell region and remove the first conductive layer at the logic region.